Current control apparatus



Jan. 26, 1954 K, A, LANG 2,667,616

CURRENT CONTROL APPARATUS Filed April 29, 195,0

ATTORNEYS.

Patented Jan. 26, 1954 "berg .Engineering "fCom ycompanyfol Illinois Ill., :assignm- .ito .'Llndpany, Chicago, I-Ill., a

.11. Claims.

This inventicnrelates' to current controlla-ppa- -ratusand more particularly toa resonantfconstant 'potential to constant -current circuit; in which provisions are `made to compensate "for'the eiect of source voltage changes.

Resonant type current regulators e employing -a zmon'ocyclic "square or a similar resonant circuit vhave'loeenemployed extensively, and itis -known `that they produce an increase in the load Y'current in V`response to anincrease in source voltage.

Various methods of compensatingior this 'characteristic vofthe circuits Ahave been employed, including those more particularly described and 'claimed' in my Patents Nos. '2;426;937-and'2,47`1;822. `In these circuits'the eiiect of the capacitatorsv is varied inresponse to supply voltage changes'to maintain the load current constant. The present "invention provides different `means for :accomplishing this result which produces yadditional 'advantages for certain types of operation.

'It is one of the objects of the presentiinven'- tion to provide a rcurrent regulating apparatus in which the inductive elements in the resonant circuit are varied inresponse to changes 4in the supply voltage. The control is such that the inl..

ductive effect varies inversely to the supply'vo'lt`- age to provide proper rvoltage compensation.

Another 'object Vis to provide a ycurrent control apparatus in which saturation of a core'on which the inductive 'windings are mounted is varied in response to supply voltage changes to compensate forsuch changes. Preferably the'core carries two saturating windings, the current'throug'h which Vis varied in a different manner in 'response `to source voltage changes so `that saturation of the core varies inversely to the voltage 4change/s.

Still another object is to provide `a current regulating apparatus in which both the capacitative andlinductive elements in the resonant circuit, are varied simultaneously in Vresponse to voltage changes. 'With this "arrangement `the `'circuit .maintained 'at "resonance, or 'substantially "at resonance, under all operating conditions.

A further Objectis to `proviclea 'currentc'ontrol apparatu'siinwhich the capacitativeelements are connected across windings mounted "on 'a core andthe inductive 'elements are formed by windings mounted on a coreand :saturation di yboth cores is simultaneously controlled Ain 're sponse'to'sourc'e voltage changes. v

The above and other 'objects A'and advantages 'of the invention will lbe nfio'reread'ily apparent from the'following'description when read l'in Y'connection withithe accompanying drawing in which;

VFigure 1"i's 'a circuit diagram of Vone 'form'of Jisprovided with 2a center fsaturatilng wwindings F9 and 21. .forms a" biasing winding Whosefeiiectfis normally fgreate'r thanrthat "of the winding #current reflect.

similar to that 32.452415822'and comprises :a1-.full `wave rectier 26 vcont:ected.across .thesupply'source..I 0,11 Jiin/series currentv control apparatusembodying'theinven '".tionfiand .control E apparatus.

'iReferringfrstfito Figure 1,''thefcircuit illus"- cludes wires-"1l D v4and Iiwhichtmayilead r`from any vconvenient generator 'ofalterna'ting cu'r'rerit'and of electric. lamps i2 The mohocyclic square includes @a irpair` iofV inductive windings l 3 and i4 wound'onva magnetic core 'lwliich is fipre'ferably provided :withfair gaps -I 6. iCondensers il and '18 `"are@connected "with the 'windings i3 and I4 in a monocyclic square circuit. Thesup- :plyleads 'Hland l l'are connected to -opposite -cor- `ners ftth'e Asquareas shownfand the :load circuit Yisfconn'ected facross the l.remaining corners "With ithis type Voffcircuit the load current will jvary'in `response to 'changes `inthe'source voltage. "Io'f'compe'nsate for thiseffectythecore i5 ileg -carrying *af pairI of The Vwinding '2 I i9. `As "shown, fthe I:Wind-ing -f2i `fis supplied lwith 'saturating cui'- 1rent-frorn avfullwwave rectifier 2'2-supplied 'from a :transformer #23 `whose 'primary Winding is connriecteddire'ctlyracross th'elsourcei', H. With this ,typefof =connection "the :saturating current Tin `the winding 21 will var-#Substantially linearly with fvoltage1:changes:=inthefsupply `source.

.The winding fllopposes the winding 2| and is supplied from the source-through -a circuit arranged vtoprovide an "amplify-ing orf-non-linear This `(circuit, fas illustrated, is disclosed .in -.-my :Patent No.

with-la saturable @reactor IV'26. vThe .rectifier .may lbeshuntedby-.avariable.resistor 26 which canbe adjusted :tov control `the 'saturating current l and which functions `to`limit the isaturating current. Normally the current through the winding i3 is so rla'ted'to that through :the winding 2l that the effect 'of' the winding I9`i's lessthan and is in .opposition to that of the winding 2 I.

In operation,'assumin'gfan fin'crease in voltage controlled. As shown, the apparatus is supplied from a source including leads 3l and 32 and supplies a load again indicated as a plurality of electric lamps 33 connected in series. The circuit includes a pair of inductive windings 34 and 35 mounted on a core 36. The core 3S carries a central leg on which saturating windings 31 and 3B are wound. One of the connections to the winding 38 may include trated, so that the effective number of turns in this winding can be adjusted. f

The capacitative elements of the circuit include a pair of windings 4l and 42 wound on a core 43 and inductively coupled through the core.

Condensers 44 and 45 are connected across the windings 4| and 42, respectively, and may include adjustable wipers 46 by which the number of turns across which the condensers are connected can be adjusted. This part of the circuit is substantially similar to that more particularly disclosed and claimed in my Patents 2,405,837 and 2,426,937.

The core 43 carries a central saturating leg on which a saturating winding 41 is wound. An adjustable wiper 48 may engage this winding so that the effective number of turns therein can be adjusted.

The winding 31 on the core 3G corresponds to the winding 2| of Figure 1 and is supplied from a full wave rectier 49 connected across the lines 3| and 32 through a transformer 5|. Thus the current in the winding 31 will vary substantially linearly in response to source voltage changes.

The saturating windings 38 and 41 are supplied with saturating current at an amplified rate in response to source voltage changes. As shown, the saturating current is suppled by a rectifier 52 connected across Jfhe source in series with a saturable reactor 53. One side of the rectifier is connected to one end of the winding 41 and the other side is connected to one end of the winding 38 and the two wipers 39 and 48 are interconnected so that the windings 33 and 41 are in series. This type of connection insures equal saturating currents in both windings, although parallel connections could be used if desired.

In the operation of this circuit the inductive effect is changed in response to source voltage changes in the same manner as described in Figure l. At the same time the core 43 is variably saturated t0 change the effect of the capacitator elements. By proper design of the components, the inductive and capacitative functions can be made to change such amounts that the output movement will be held constant and the circuit will be maintained in resonance to provide a unity, or near unity, power factor under all operating conditions.

While two embodiments of the invention have been shown and described in detail, it will be understood that these are illustrative only and not to be taken as a definition of the scope of the invention, reference being lhad for this purpose to the appended claims. y

a movable wiper 39, as illus- What is claimed is:

1. Current regulating apparatus comprising a pair of inductive windings and a pair of capacitors connected in a monocyclic square opposite corners of which are adapted to be connected to an alternating current source and the remaining corners to a load, a core on which the inductive windings are wound, a saturating winding on the core, and means connecting the saturating winding to the source to supply variable saturating current thereto in response to the source voltage.

2. Current regulating apparatus comprising a pair of inductive windings and a pair of capacitors connected in a monocyclic square opposite corners of which are adapted to be connected to an alternating current source and the remaining corners to a load, a core on which the inductive windings are wound, saturating windings on the core, and means separately connecting the saturating windings to the source to supply variable saturating current to the windings in response to the source voltage to vary saturation oi the core inversely to changes in the source voltage.

3. Current regulating apparatus comprising a pair of inductive windings and a pair of capacitors connected in a monocyclic square opposite corners of which are adapted to be connected to an alternating current source and the remaining corners to a load, a core on which the inductive windings are wound, a pair of saturating windings on the core, and means separately connecting the saturating windings to the source to supply variable saturating current thereto in response to the source voltage, said means having diierent voltage response characteristics and being connected to the saturating windings in opposition to each other to produce a resultant change in saturating current inverse to voltage changes in the source.

4. Current regulating apparatus comprising a pair of inductive windings and a pair of capacitors connected in a monocyclic square opposite corners of which are adapted to be connected to an alternating current source and the remaining corners to a load, a core on which the inductive windings are wound, a pair of saturating windings on the core, a rectier connecting one of the windings to the source to produce a substantially linear change in the saturating current therein in response to the source voltage, a circuit including a rectifier connecting the other saturating winding to the source in opposition to said one of the windings, and amplifying means in the circuit to produce a non-linear response to changes in the source voltage.

5. Current regulating apparatus comprising a pair of inductive windings and a pair of capacitors connected in a monocyclic square opposite corners of which are adapted to be connected to an alternating current source and the remaining corners to a load, a core on which the inductive windings are wound, a pair of saturating windings on the core, a rectier connecting one of the windings to the source to produce a substantially linear change in the saturating current therein in response to the source voltage, a circuit including a rectier connecting the other saturating winding to the source in opposition to said one of the windings, and a saturable reactor in the circuit to produce a non-linear response to changes in the source voltage.

6. Current control apparatus comprising a pair of inductively coupled windings wound on a core, a capacitor connected across at least one of the windings, a pair of inductive windings wound on a second core and connected to the coupled windings in a. monocyclc square, opposite corners of which are adapted to be connected to an alter nating current source and the remaining con ners to a load, saturating windings on the cores, and means connecting the saturating windings to the source to vary the saturating current therein in response to the source voltage.

7. Current control apparatus comprising a pair of induotively coupled windings wound on a core, a capacitor connected across at least one of the windings, a pair of inductive windings wound on a second core and connected to the coupled windings in a monocyclic square, opposite corners of which are adapted to be connected to an alternating current source and the remaining corners to a load, saturating windings on the cores, and means connecting the saturating windings to the source and effective to vary the sau urating current therein opposite directions in response to changes in the source voltage.

8. Current control apparatus comprising a pair of inductively coupled windings wound on a core, a capacitor connected across at least one of the windings, a pair of inductive windings wound on a second core and connected to the coupled windings in a monocyclic square, opposite corners of which are adapted to be connected to an alternating current source and the remaining corners to a load, a saturating winding on the first core, a pair of saturating windings on the second core, a rectier connecting one of the pair of saturating windings to the source, a circuit including a rectier connecting the other two saturating windings to the source, and means in the circuit to produce a non-linear response to changes in the source voltage.

9. Current control apparatus comprising a pair of inductively coupled windings wound on a core, a capacitor connected across at least one of the windings, on a. second core and connected to the coupled 4 a pair of inductive windings wound windings in a monocyclic square, opposite corners of which are adapted to be connected to an altermating current source and the remaining corners to a load, a saturating winding on the first core, a pair of saturating windings on the second core, a rectier connecting one of the pair of saturating windings to the source, a circuit including a rectier connecting the other two saturating windings to the source, and a saturable reactor in the circuit to produce a non-linear response to changes in the source voltage.

10. Current regulating apparatus comprising a pair of inductive elements and a pair of capacitor elements connected in a monocyclic square adapted to have opposite corners connected to an al= ternating current source and the remaining corners to a load, means to vary the inductive effect of the inductive elements, and control means responsive to the source voltage to control the last named means to produce changes in the inductive eiect inverse to source voltage changes.

l1. Current regulating apparatus comprising a pair of inductive elements and a pair of capacitor elements connected in a monocyclic square adapted to have opposite corners connected to an alternating current source and the remaining corners to a load, means to vary the inductive eiTect of the inductive elements, means to vary the capacity eiect source voltage to produce changes in both of said effects inverse to source voltage changes.

KARL A. LANG.

References Cited in the le Of this patent UNITED STATES PATENTS 

